Grass advice: Key breeding and management decisions for May

The first round of breeding has kicked off to a flying start, with excellent weather over the past few weeks.

I observe the cows at least three times a day as this will enhance breeding performance.

The best times I believe to check cows are before morning milking, between 10:00am and 1:00pm, and before evening milking. Another good time is 9:00pm, but this won’t suit everyone.

However, checking cows just after milking is of little benefit as they express the least activity at this time.

In April, I talked about scanning non-cycling cows since it is important to note if they have cycled since scanning. When mating these cows I would recommend using beef straws.

It is not advised to breed from ‘problem cows’, irrespective of how good the AI bull is.

Grass management

Depending on the variety, grass will begin showing a seed head from May 25 onward.

The seed head is making its way up the grass plant now so having low-moderate pre-grazing covers of 1200-1400kg DM/ha and residuals as close to zero as possible, is the only way to maintain quality.

Energy levels in grass are dictated by the leaf-to-stem ratio. The greater the stem content, the lower the energy.

A rotation length of 18-20 days should be targeted, with approximately 170kg cover/cow.

Any excess grass should be removed as soon as the weather permits. This helps to ensure pre-grazing sward quality is maintained.

grass breedingIf cows are put into high-quality covers and hit the target residuals, they will be fully fed on a high-energy diet both then and in the next rotation. This will maximise conception rates.

In contrast, if we chase milk yield and slacken residuals, financial gain will be short-term.

Subsequent rotations of poor-quality grass will reduce kilograms of milk solids produced and fertility performance.

With growth rates averaging 90-100kg/day for the past two weeks, we took out some surplus paddocks last week.

Pre-grazing quality is excellent, but there is stem appearing in some paddocks. For this reason we are following quality and not the wedge – for example, if a paddock with a cover of 1200kg had some stem coming through, we would graze it before the highest cover. This has a huge benefit for the quality of the next rotation.

Obviously not all paddocks can be grazed before the grass heading date, but surpluses arising when the weather improves again will remove these.

Key points:
  • Target submission rates: 45-50% by day 12 and 90-100% by day 24.
  • 150-170kg cover/cow.
  • Walk the farm every five to seven days. Look at the base of the sward to identify where the stem is.
  • Use a beef bull when breeding late calvers or cows that needed intervention to cycle.